Erlotinib in Treating Patients With Recurrent Glioblastoma Multiforme or Gliosarcoma

OBJECTIVES: Primary * Determine the objective response rate in patients with recurrent epidermal growth factor receptor (EGFR)-positive and PTEN wild-type glioblastoma multiforme or gliosarcoma treated with erlotinib hydrochloride. Secondary * Assess the response rate in patients who also EGFRVIII mutant and PTEN wild type glioblastoma multiforme or gliosarcoma. * Determine the progression-free survival of patients treated with this drug. OUTLINE: This is an open-label study. Patients are stratified according to concurrent use of enzyme-inducing antiepileptic drugs (EIAEDs) (yes vs no). Patients receive oral erlotinib hydrochloride once daily on days 1-28. Treatment repeats every 4 weeks for up to 1 year in the absence of disease progression or unacceptable toxicity. Some patients may receive additional erlotinib hydrochloride after 1 year at their physician's discretion. After completion of study treatment, patients are followed periodically. PROJECTED ACCRUAL: A total of 30 patients will be accrued for this study.